Device for applying a strengthening patch to a square-bottom-bag



Jan. 15', 1957 L. K DEVICE FOR APPLYING A OOP 2,777,368

STRENGTHENING PATCH TO A SQUARE-BOTTOM-BAG Filed Feb.

, Inventor:

LAmgs K00 P United States Patent DEVICE FOR APPLYING A STRENGTHENING PATCH TO A SQUARE-BOTTOM-BAG Lambert Koop, Bielefeld, Germany, assignor to Messrs.

Fischer & Krecke (Maschinenfabrik), Bielefeld, Germany,

Application February 17, 1954, Serial No. 410,979

4 Claims. (Cl. 93--8) The invention relates to a device in a square-bottombag-forming-machine with means for opening and forming the bottom from a tubular blank for machine made applying of a bag bottom strengthening patch to the bottom side flaps of the bag. The patch is applied to the bag-bottom and connected with the bag bottom flaps of the bag from the inside of the bag during the folding of the bag bottom. The patch forms a strengthening and in addition a seal against penetration of filling material of the bag from the inside of the bag into the individual layers of the bag bottom.

It is known to place strengthening strips on the bag bottom square and then effect as folding over of the bag bottom flaps but this does not prevent the filling material from being able to penetrate the individual 7 layers of the bag bottom.

By means of the present invention a strengthening patch placed in the pro-opened square-bottom of a squarebottom bag from the inside of the bag bridges the gap remaining between the side flaps whereby it is stuck over the whole width of the bottom including the bottom flaps to be bent over, to both edges of the side flaps adjacent the gap.

The means for the applying of the strengthening patch by machine to the bottom side flaps from the inside of the bag is so arranged on the machine that the strengthening patch is introduced by means of an applying roller with a width less than the distance of the gluing strips from one another and pneumatic or mechanical holding and guiding means in the area of the bagbottom opening arrangements, to the pre-opened bottom and stuck to same from the inside of the bag. The arrangement for the applying of the patch consists essentially of a roller, drawing 01f means, cutting means, adhesive depositing means and guide means for the cut off patches.

Further details of the invention are explained more fully in the following description in conjunction with the drawing.

In the drawing one example of the patch applying device on a square bottom bag machine, is illustrated diagrammatically.

Fig. 1 shows one embodiment of the applying device in side view,

Fig. 2 shows the applying roller in disc-like shape with the strengthening patches, in plan.

Fig. 3 shows a cross bottom bag still open with the inserted strengthening patch.

Fig. 4 shows a still open block bottom bag with an inserted strengthening patch.

As seen from Fig. l, the tubular blank 1 is led to the rollers 2 and 3 of the square-bag-forming machine and in known manner the bag bottom square is laid and formed over the nose piece 4.

A paper band 6 is drawn otf from the paper roll over the draw rollers 7, 8 and led to the cutting mechanism with rollers 9, 10. The cutting knife 11 on the roller cooperates with a counter-groove 12 with a bottom flaps to be bent over.

ice

suitable flexible cover on the roller 9 and cuts otf a strengthening patch 21 from the paper band 6. This cutoff patch 21 is conducted by means of the needle 13 of the roller 9 to the paste depositing roller 14 which applies two parallel gluing strips 15 on the patch 21. The paste roller 14 receives the adhesive from the roller 16 out of the paste through 17. The strengthening patch 21 thus provided with gluing strip 15 is drawn from the roller 9 by means of a stationary guide 22 and over a narrow applying disc or roller 18 in contact with the roller 9, applied into the bottom square 19 and stuck to same at the edges of the bag bottom opening. The applying roller 18 is kept so narrow that the sticking strips 15 on the strengthening path 21 do not come into contact with the disc periphery and the applying roller 18 does not obstruct the bag bottom. The strengthening patch 21 is held at the periphery of the applying roller 18 by means of suction openings at the outer end of suction channels 20. The guide 22 liftsthe strengthening patches 21 from the needle 13 of the cutting cyl-v inder 9 and guides it for its applying into the interior of the bag and to the inside of the bottom flaps. Instead of the suction openings of suction channels 20, needles may be placed on the applying roller or disc 18. The strengthening and sealing patchzl applied into the bag interior is stuck to both opening edges of the side flap 23, 24 over the whole width of the bag bottom including the It prevents the penetra tion of filling material between the individual layers of the bag bottom and effects substantially better strengthening of same.

What I claim is:

1. In a square-bottom-bag forming machine with means for opening and forming the bottom from a tubular blank, a device for applying a bag bottom strengthening patch to the bottom side-flaps of the bag, comprising means for feeding and cutting off a single bag bottom strengthening patch from a paper band, means to provide said patch on one side with two parallel gluing strips at a distance from one another, an applying roller for said patch having a width less than the distance of the gluing strips on said patch from one another, holding means on said applying roller for said patch acting on the side of and between said gluing strips upon said patch, a guide for said patch at the opposite side of the gluing strips cooperating with said applying roller, said guide and said applying roller being disposed in the area of said bottom opening and forming means of said square-bottom-bag forming machine and cooperating with these means during the folding of the bottom flaps and the forming of the bag bottom in such a manner that said strengthening patch is applied at first to the inside of the bag with the gluing strip facing the underside of the bag bottom flaps and then adhered to said flaps from the inside of the bag.

2. In a square-bottom-bag forming machine, means for opening and forming the square bottom from a tubular blank and a device for applying a bag bottom strengthening patch to the bottom side-flaps, comprising a paper band roll, means for drawing a paper band from said roll, means for cutting off a single strengthening patch from said paper band, consisting of two rollers, a cutting knife carried by one of said rollers and a corresponding groove with a flexible covering on the other of said rollers, needles on said groove roller forholding said strength ening patch, means for depositing parallel gluing strips on one side of each of said strengthening patches at a roller and means for supplying said strengthening patch to the inside of said bottom-flaps, consisting of an applying roller and a stationary guide cooperating with said applying roller, the latter and said guide being arranged within the reach of the bag bottom opening means of the machine for applying said strengthening patch to the bottom flaps from the inside of the'bag.

3. In a squarc-bottorn-bag forming machine a device as per claim 2, in which said applying roller is in cooperative connection with said groove roller, said stationary guide being arranged concentrically to said applying roller and spaced from the periphery of said applying roller extending within the reach of said groove roller for simultaneously effecting lifting off the strength ening patch from the holding needles of said groove roller. t

4. In a square-bottom-bagforming machine a device as per claim 2, in which suction channels are arranged within said applying roller and suction openings being 4 disposed at the outer ends of said suction channels adapted to hold the strengthening patch on the periphery of said applying roller, said stationary guide being disposed concentrically to said applying roller and spaced from the periphery of the applying roller, extending within the reach of said groove roller for the lifting of the strengthening patch from the holding needles of said groove roller when said patch passes from the groove roller to the applying roller.

References Cited in the tile of this patent UNITED STATES PATENTS 714,386 Matteson Nov. 25, 1902 1,721,399 Klein July 16, 1929 2,070,205 Heywood Feb. 9, 1937 2,125,308 Novick Aug. 2, 1938 

